Ensure global .NET trust level is configured

MediumLevel 1Automatediis

Description

An application's trust level determines the permissions that are granted by the ASP.NET code access security (CAS) policy. CAS defines two trust categories: full trust and partial trust. An application that has full trust permissions may access all resource types on a server and perform privileged operations, while applications that run with partial trust have varying levels of operating permissions and access to ... The global .NET trust level (root web.config) must be Medium (Low and Minimal are stricter and also accepted); the default Full fails. PowerShell 5.1 with the WebAdministration module; run elevated.

How it is checked

Audit method: Shell command

shell

Import-Module WebAdministration -ErrorAction Stop; $c = Get-WebConfiguration -Filter 'system.web/trust' -PSPath 'MACHINE/WEBROOT'; if ([string]$c.level -in @('Medium', 'Low', 'Minimal')) { 'compliant' } else { 'noncompliant' }

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Set-WebConfigurationProperty -PSPath 'MACHINE/WEBROOT' -Filter system.web/trust -Name level -Value Medium

Properties

Operating systems: Any
Tags: iisaspnet
Reference: CIS Microsoft IIS 10 Benchmark v1.2.1 - 3.10 Ensure global .NET trust level is configured

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target iis